# Tag Info

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Physicist137 took a crack at showing why this follows from the structure of the electric field in the absence of time-dependent magnetic fields. That doesn't hold once you have induction in the system, however. So let's look at a simpler approach. Anything that you want to treat as a potential (whether it is a real potential or not) has to have a simple ...

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After $5 \tau$, the voltage across the capacitor is about $.7$% of what it was originally. There are definitely situations where this $.7$% could be significant, so when the problem says you can consider this voltage to be zero, it probably means that the accuracy of any tool you would use to measure the system is low enough that it wouldn't be able to ...

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It depends. The time evolution stays the same: $V(t)=V_0 e^{-5}e^{-t/\tau}$, the "non stabilized" part of the total voltage is just smaller. Often this part is considered constant for practical purposes.

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The answer is "maybe" and you will not know which one to adjust, if any, without a circuit diagram. Just record their positions so you can undo any changes you make, and experiment. As you said - it's cheap.

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You seem to be asking about mode transformers; these are extensively used in antennas as they connect to waveguide feeds. The waveguides usually employ TE10 (rectangular) or TE11 (circular) modes, but if you want to feed a horn, say, then you have to shape the field properly to avoid reflection, reduce sidelobes, and reduce cross-polarization coupling, etc. ...

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Pneumatic circuit components are close to what you are looking for. You can buy pneumatic components that allow you to do a wide variety of operations online from places like McMaster-Carr, or directly from the manufacturer, e.g., from Clippard. I'm not so sure there are too many off-the-shelf components that are direct analogues to a particular electrical ...

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The live found a route to earth, discharging it's energy on whatever load was connected between live and earth, and then luckily the RCD cut off the supply before you cooked yourself.

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I guess the question is whether the LED will also act as a photodiode, i.e. whether incident light will excite electrons and therefore generate a current. If so, then reflect the diodes light back onto it will indeed reduce the current flowing in the diode by generating an opposing EMF. This turns out to be surprisingly hard to Google, but Wikipedia ...

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Hyper physics website says this Electric current flow is proportional to voltage difference according to Ohm's law, and both the bird's feet are at the same voltage. Since currentflow is necessary for electric shock, the bird is quite safe unless it simultaneously touches another wire with a different voltage. ...

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One should really be careful when mixing circuit theory and electromagnetic theory... Fact of the matter is, circuit theory is a much simplified version of electromagnetism. In circuit theory, we speak of the "voltage" of a point, in reference to the ground, and act like it is a well-defined quantity. In fact, what is called the electrical potential is ...

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The rotational of the electric field: $$\nabla\times\mathbf E = -\frac{\partial\mathbf B}{\partial t}$$ Using Stokes' Theorem on this equation, we get the integral form of this equation: $$\varepsilon = \oint_{\gamma}\mathbf E\cdot\mathbf{dl} = -\frac{d}{dt}\iint_S\mathbf B\cdot\mathbf{dS} = -\frac{d\Phi}{dt}$$ Which means, the electric field in a ...

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